In this follow up article to last weeks
Danger
in Space, Sir Martin Rees reflects on the recent space tragedy,
and ponders the question of the dangers of men travelling into space.

by Sir Martin Rees, Astronomer
Royal

Space is an unexplored
frontier. The fate of the Space Shuttle Columbia reminds us that
those who venture beyond the Earth confront real danger. The astronauts
themselves have always been mindful of the hazards. I recall attending
a lecture given, back in the 1960s, by John Glenn, the first American
to go into orbit. A questioner asked him what went through his mind
while he was crouched in the rocket nose-cone, awaiting blastoff.
He wryly replied " I was thinking that the rocket had twenty
thousand components, and each was made by the lowest bidder".
Glenn survived to become a US senator, as well as an inspiration
to elderly Americans when he ventured into space again, at age 77.

Other astronauts have
been less lucky. There were probably fatalities in the early Soviet
space ventures, though these were never publicised at the time;
three of Glenn's fellow-astronauts perished while testing NASA's
Apollo capsule; the near disaster that befell James Lovell and his
crew in Apollo 13 is familiar to a younger generation through the
excellent film starring Tom Hanks. An earlier shuttle, the Challenger,
exploded, killing its crew, in 1986.

John Glenn was aware
of the risk he was taking - so surely, would have been the astronauts
who perished last Saturday. But their fate injects a dose of reality:
space travel is not a routine exercise. We need to ask - as we do
of any pioneering venture - whether the goals of manned spaceflight
are inspiring or valuable enough to justify the hazards involved.
The Shuttle's 98 percent success record - two catastrophic failures
in just over a hundred flights - is actually rather good by space
standards. Must unmanned rockets have a worse record. (The French
Ariane V rocket had two catastrophic failures in less than a dozen
flights). We don't yet know whether last week's accident could have
been avoided by better maintenance. I suspect it could. But even
with optimal precautions, the risks of going into space will remain
high compared to those that most of us willingly and routinely accept.

When the Challenger
exploded in 1986, the trauma was deepened because one of those killed
was a schoolteacher, Christa McCauliffe. The American public had
been falsely lulled into a view that spaceflight was 'routine' and
that astronauts faced little more risk than passengers in a commercial
jet. But the memory of that accident had faded and Americans had
come to believe that space was a place for tourists. Publicly-funded
astronauts are, in a sense, acting on our behalf. We feel uneasy
about civilians bearing such risks, when the issues aren't of life
or death urgency, but primarily science or exploration. Nonetheless,
some individuals - wealthy amateur mountaineers who join guided
parties to climb Everest, or test pilots - willingly do things that
are at least as dangerous as a Shuttle flight.

NASA

Hurtling
out of the conflagration at 78 seconds are the Challenger's
left wing, main engines (still burning residual propellant)
and the forward fuselage (crew cabin).

When I am asked about
the case for sending people into space, my answer is that as a scientist
I'm against it, but as a human being I'm in favour. Practical activities
in space - for communications, science, weather forecasting and
navigation (including the marvellous GPS system) - are better (and
far more cheaply) carried out by computers and robots. I am nonetheless
an enthusiast for space exploration as a long-range adventure for
(at least a few) humans . The next humans to walk on the Moon may
be Chinese - only China seems to have the resources, the dirigiste
government, and the willingness to undertake a risky Apollo-style
programme. I hope Americans or Europeans will sometime venture to
the Moon and beyond, but this will be in a very different style,
and with different motives.

The kind of vibrant
manned programme that I'd one day like to see will require changes
in techniques and style. First, costs must come down. Present procedures
are as extravagant as air travel would be if the plane had to be
rebuilt after every flight; the Space Station is cumbersome and
inflexible. Second, there must be an overt acceptance that the enterprise
is dangerous. A role model for the future astronaut is not a NASA
employee, nor even a military test pilot, but someone more in the
mould of Steve Fossett, the wealthy 'serial adventurer' who, after
several expensive failures, succeeded in his solo round-the-world
balloon flight. He has (like our own Richard Branson) a craving
for arduous challenges , and is now trying to beat altitude and
endurance records for gliders.

NASA

Touring
the Johnson Space Center on a familiarization tour, from
left to right, are backup Soyuz 4 Commander Cosmonaut Gennady
Padalka, a Russian cosmonaut; Soyuz 4 Space Flight Participant
Mark Shuttleworth, a South African businessman who flew
to the International Space Station.

In each venture, Fossett
must knowingly accept a risk of at least 1 percent. Were he to come
to a sad end, we would mourn a brave and resourceful man, but there
would not be a national trauma. We would know that he willingly
too the risks, and it was perhaps the way he wanted to go. Future
expeditions to the Moon and beyond will only, I think be politically
and financially feasible if they are spearheaded by individuals
prepared to accept high risks. American financier Dennis Tito and
the South African software magnate Mark Shuttleworth each spent
20 million dollars in return for a week in the International Space
Station. A line-up of others was willing to follow them, even at
that price. Such people won't, in the long run, restrict themselves
to the role of passengers passively circling the Earth: they will
yearn to go further.

Manned expeditions
into deep space may one day be fundable by private consortia. Larry
Ellison, the multi-billionaire CEO of Oracle who bankrolled a yachting
challenge for the Americas Cup would already have the resources
to initiate a project to explore the Moon and beyond. The maverick
engineer Robert Zubrin has proposed a cut-price Mars mission for
ten billion dollars. In earlier centuries, adventurers explored
the then-open frontiers of our own world. Columbus, Magellan, and
the other intrepid voyagers who set out from Europe in the 15th
and 16th century were mainly bankrolled by monarchs, in the hope
of recouping exotic merchandise or colonising new territory. Some
later expeditions, for instance Captain Cook's three 18th century
voyages to the South Seas, were publicly funded, their mission being
to survey new territory, discover new plants, and make astronomical
measurements.

For some early explorers
- generally the most foolhardy of all - the enterprise was primarily
a challenge and adventure: the motivation of present-day mountaineers,
balloonists, round-the-world sailors and the like. Many of these
explorers never returned. Even when they did, their crews had suffered
severe attrition through disease and accident. The first travellers
to Mars (maybe thirty years from now), or the first long-term denizens
of a lunar base, could be impelled by this same range of motives.
The risks would be high. However, no space travellers would be venturing
into the unknown to the extent that the great terrestrial navigators
were.: Those early pioneers had far less foreknowledge of what they
might encounter in the regions where ancient cartographers wrote
"here be dragons".

Artist Pat
Rawlings' concept of the type of work and hazards future
astronauts will encounter on outer worlds: Mars Rover Repair

Nor would space travellers
be denied contact with home, any more than explorers and lone sailors
now are. There would admittedly be about a 30 minute turnaround
for messages to and from Mars, because it takes that long for a
radio signal to traverse the hundreds of millions of miles distance.
But that is as nothing compared to the isolation of traditional
explorers. It generally took months for them to send messages home;
and the heroism of some - Captain Scott and other polar pioneers
among them - is known to us only because their diaries survived.

The exploration will
never involve more than a tiny number - it is absurd to regard emigration
into space as a solution to population pressure on Earth. Neither
Mars nor anyone else in our Solar system offers an environment even
as clement as the Antarctic or the deep ocean. But, as in pristine
parts of our own Earth, any human presence leads to issues of environmental
ethics. Would it be acceptable to exploit Mars, as happened when
(with tragic consequences for the Native Americans) the pioneers
advanced westward across the United States? Or should it be preserved
as a natural wilderness, like the Antarctic? The answer would I
think depend on what the pristine state of Mars actually is. If
there were any life there already then there would be widely voiced
views that it should be preserved as unpolluted as possible. What
might actually happen would depend on the character of the first
expeditions. If they were governmental (or international), Antarctic-style
restraint might be feasible. On the other hand, if the explorers
were privately funded adventurers of a free-enterprise (even anarchic)
disposition, the Wild West model would be more likely to prevail.

The stakes will be
high for space explorers: they will be opening up entire new worlds.
Maybe some would accept - as many Europeans willingly did when they
set out for the New World -- that there would be no return. Many
could be found who would sacrifice themselves in a glorious and
historic cause; by foregoing the option of ever coming back home.
A Martian base would develop more quickly if those constructing
it were content with one way tickets.

The mountaineers George
Mallory and Andrew Irvine both perished on Mount Everest in 1924,
during a celebrated early attempt to reach its summit. A stone tablet
in Irvine's memory bears a text from the famous funeral oration
by the Athenian general Pericles in the 5th century BC: "They
are most rightly reputed valiant who perfectly understand what is
dangerous and what is easy, but are not thereby diverted from adventuring".
This sentiment, I believe, would have resonated with the astronauts
who died on February 1st 2003. In future decades, if humans venture
to the Moon and beyond, they will have to go in this same spirit.